1. Field of the Invention
This invention relates to novel aziridinedicarboxylic acid derivatives, which are useful as a prophylactic and therapeutic agent of bone diseases and an agent of inhibiting thiol protease.
2. Description of Related Art
In bone tissue, bone resorption and formation occur constantly with a good balance to ensure bone homeostasis; bone diseases such as osteoporosis are caused when the balance shifts to the bone resorption side. In recent years, various epoxy compounds possessing prophylactic and therapeutic activity against bone diseases have been reported [JPA H2(1990)-218610, EP-A 269311].
However, aziridinedicarboxylic acid derivatives having prophylactic and therapeutic activity against bone diseases and activity of inhibiting thiol protease have not been reported yet.
Currently, bone resorption suppressors such as estrogens and calcitonin are used for the prophylaxis and therapy of bone diseases such as osteoporosis. However, in the case of administration of these therapeutic agents, subjects to be administered are limited and their efficacy is uncertain in some instances, and satisfactory effects have not yet been brought about. And, at the present stage, compounds showing satisfactory inhibiting action against thiol protease secreted from lysosome of osteoclasts have not yet been available.